Expand variables in `configure_options`

[petoknm]

For cross compiling ffmpeg, I needed to supply the compiler as an argument to configure. That is why I needed to add variable expansion to configure_options of configure_make rule.

configure_make(
  ...
  configure_options = [
    ...
    "--cc=$(CC)",
  ]
)

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[jsharpe]

Fixed in https://github.com/bazelbuild/rules_foreign_cc/pull/1102